Airplane liquid-spraying unit



April 9, 1963 R. E. HYDE AIRPLANE LIQUID-SPRAYING UNIT 2 Sheets-Sheet 1Filed April 16, 1959 INVENTOR.

RICHARD HYDE BY a ATTORNEY.

April 9, 1963 R. E. HYDE AIRPLANE LIQUID-SPRAYING UNIT 2 Sheets-Se FiledApril 16, 1959 INVENTOR. RICHARD E. HY E ATTORNEY United States Patent M3,084,890 AIRPLANE LIQUID-SPRAYING UNIT Richard E. Hyde, Dos Pains,Calif. Filed Apr. 16, 1259, Ser. No. 806,854

4 Claims. (Cl. 244-136) 1 This invention relates to.an airplaneliquid-spraying unit.

' When crops are sprayed with liquid insecticides, fungicides, etc.,better and more uniform coverage is obtained and less liquid is wastedwhen the liquid falls on the leaves in an even pattern and in dropletsize, instead of being dispersed in a fog or very fine mist. Theimportance of the even pattern is that an exact amount of the materialis required on each square foot of the area to be treated. Theimportance of the droplet size stems from the fact that large drops tendto touch only part of the plant, while particles of liquid ina very finemist tend to evaporate and to be blown away as they fall, so that someof the liquid never reaches the leaves of the crop being sprayed, and ingusty weather the distribution is uneven. So it takes less liquid to dothe same job and the job is done better when the spray is in an evenpattern with its particles in droplet size.

Conventional airplane spraying units suffer from the fact that thewhirling of the propeller and the passage of the wings and other partsof the plane through the air create air-flow patterns that adverselyaffect the evenness of the spray pattern and the size of the liquidparticles in the spray. The propeller blast moves air from one side ofthe airplane to the other, the direction of flow depending on thedirection of rotation of the propeller, and the air movement at the wingtip is in a vortex from the lower surface of the wing, where the air hasgreater density, around the wing tips to the upper surface of the wing,where the air has less density. Where the two varying air pressuresmeet, there is circular air movement, like a cyclone along a horizontalaxis. These air movements tend to make the spray pattern uneven and tobreak up the sprayed particles, particularly at the wing tips. Thus thespray'is'dispersed unevenly and in the form of a very fine mist.

The present invention avoids subjecting the spray droplets to this airdisturbance by issuing the spray droplets at a level below thedisturbance. The spray material is not blown away by the propeller blastor by the air currents created thereby, nor is it affected by the vortexcreated by the outward movement of air along the wing. This makes itpossible to reduce the liquid dosage per acre, both because of theresultant evenness of application and because far less is blown away.

Moreover, the present invention provides an assembly wherein the spraytubes can be raised and lowered, so that they can extend down low whenspraying and can be lifted at other times so as not to interfere withthe landing operation of the plane.

Another feature of the invention is its use of the motion of theairplane through the air to help lower the nozzles to their sprayingposition and to hold them there.

Other objects and advantages of the invention will appear from thefollowing description of a preferred embodiment thereof.

In the drawings:

FIG. 1 is a perspective view of an airplane spraying unit embodying theprinciples of the invention, shown in its spraying position, with theairplane flying.

FIG. 2 is a fragmentary view in side elevation of a portion of theairplane of FIG. 1, showing the spraying nozzles in their raised orretracted position, and also showing the lever system for rotating themand the boom which supports them.

FIG. 3 is a view in side elevation and partly in section,

3,084,890 Patented Apr. 9, 1963 on an enlarged scale, of the rotatableboom and the spraying nozzles which are supported by the boom.

FIG. 4 is a perspective view of the spraying apparatus removed from theairplane and including the spray boom, the spray nozzles, a portion ofthe spray container tank, and the pump system, together with a portionof controls for the boom position and for the valves.

FIG. 5 is a fragmentary view in side elevation, enlarged with respect toFIG. 2, showing the two principal positions of the spray nozzles. Solidlines show the nozzles in their lower, spraying position, and brokenlines show their raised, normal-flight, non-spraying position.

FIG. 1 shows an airplane 10 with a fuselage 11. The plane 10,illustrated for example only, is a biplane with a lower wing 12 and anupper wing 13. The fuselage 11 has a cockpit 14 for the pilot and, atits nose, an engine 15 and a propeller 16. The airplane 10 also has alanding gear 17 with Wheels 18 and, in conformance with conventionalcrop-spraying planes, this landing gear 17 is preferably notretractable.

An important problem solved by the present invention relates to the factthat the propeller draft creates strong air currents that tend to breakup liquid droplets. Also, the outward movement of air along the wing 12creates a kind of vortex. The resultant turbulence affects the airadjacent the wings and propeller for a substantial distance below andabove, so that where the spray nozzles are located closely adjacent tothe wing, the spray is ejected into the turbulent airstream and brokenup, thereby impairing the efiiciency of the operation.

In the present invention, the spray unit (see FIG. 4 especially)includes a rotatable hollow boom or manifold 20 from which project aseries of nozzle tubes 21 of sub stantial length. In their normal,non-spraying position these nozzles tubes 21 extend generallyhorizon-tally and rearwardly from the boom 20 as in FIGS. 2-4 and inbroken lines in FIG. 5, but in spraying position they extend downwardlyto a point beyond the area of turbulence adjacent the Wings andpreferably below the landing gear 17 and its wheels 18, as shown in FIG.1 and in solid lines in FIG. 5.

The boom 20 may be supported from the lower surface of the wing 12 andbelow the fuselage 11 by a series of vertical columns 22 with supportingbrackets 23 secured to their upper end and to the lower surface of theWing 12. Also, adjacent the outer ends of the boom 20 there may be bentcolumns 24 that are secured to upper wing 13, for additional support.Collars 25- are clamped securely around the boom 20 and are providedwith cranks 26 which are pivotally secured to the lower ends of thecolumns 22 and 24 by pintles27, so that the boom 20 is rotatable aboutrelative to its supporting columns 22 and 24.

As shown in FIG. 2, a lever handle 28 is supported at one side of thefuselage 11 adjacent the cockpit 14 where the pilot can easily controlit manually. The lever 28 is connected by links 29 and 30 and a cable 31pivotally to a crank 32 that is secured rigidly to the rotatable boom20. The lever 28 is provided with a lock 33 normally holding it in itsrearward position when the crank 32 and nozzles 21 are horizontal.

A pair of vanes 34 are attached at the outer ends of rods 35, which arerigidly attached to the boom 20*. When the pilot releases the leverhandle 28 from the lock 33 :and moves it forward, the vanes 34 begin tolift from their normally horizontal position (FIG. 4) and to interceptthe wind. The force exerted against them by the wind helps to rotatethem and the boom 20 to their upward, nearly vertical, position (FIG 1)in which the nozzles 21 are in their lower position with their tips 36below the turbulent area. The pilot can raise the boom 20 simply bypulling the handle 28 back, thereby lowering the vanes 34 to theirhorizontal position and placing the nozzles 21 horizontal. The vanes 34also help inform the pilot Whether the nozzles 21 are up or down.

It will be noted, particularly from FIG. 3, that instead ofmerely-connectingthe nozzle tubes 21 directly to the manifold boom 20,the connection is made through a valve 37; The valve 37 includes aninlet fitting 38 that is connected to the interior passage. 39 of themanifold boom 20, andan outlet fitting 40 that is connected to thenozzle tube 21 by ashortconnecting tube 41. Adjacent the outlet 40' is:1 valve seat, 42 against which a movable valve member 43. closes whenthe valve 37 is in its closed position, The valve closure member 43 isconnected by a stem 44 to a diaphragm 45. A perforate cover member 46protects the atmospheric side of the diaphragm 45, and an opening 47-through the cover 46 aifords maintenance of atmospheric pressure air onone side of the diaphragm 45. From this itfwill be obvious thatatmospheric pressure always tends to move the diaphragm 45 to a positionwhere the valve member 43 restsagainst the seat 42 and therefore closesthe valve 37. However, when fluid under pressure (i.e., the liquid to'besprayed, when itisbeing pumped) enters the inlet 38-it flows into achamber 48 and, as pressure builds up, counteracts the atmosphericpressure on the diaphragm 45 and therefore opens the valve 37 by movingthe closure member 43 away from the seat 42. This arrangement assuresthat there will be no dripping of liquid through the nozzles 21 when nospraying is being done.

The spray solution itself is preferably retainedin a tank 50having anoutlettube 51 that leads to a pump 52 whose pump element is connected bya shaft 53 to a fan 54 The fan 54 is driven by air when the airplane isin flight, and its rotation operates through the pump 52.. In otherwords, the pump 52 is driven by the movement of the plane 10 through theair, so that no separate motor is needed and there is no extra load onthe airplane, engine 15.

From the pump 52 an outlet tube, 55 leadsto a T 56, whence one conduit57 leadsvia a valve 58 back to the tank 50. Another conduit 60,1eadsto avalve 61- and from there through tubes 62 and 63 into the manifoldb-oompassage 39. i

' A lever 64 is preferably mounted by a center pivot 65 on the tube 55.One end 66 of the lever 64 is connected by a 'linkl67 to a crank 68which opens and closes the valve 58. The. other end70is connected by alink 71 to a crank-arm 72 which opens and shuts the valve 61. The leversandlinks are arrangedtoopen the. valve 61 when the valve58 is closed and.vice versa. Moreover, the link 71 is connected by a cable 73 to acontrol member (not shown) in or adjacent the cockpit 1.4.. When thevalve 58; is open, the valve61 is closed, so that the pump 52 thenmerely circulates the spray liquid from the bottom of't-he tank 56around and back intothe tank 50, via conduits 5-1, 55, and 57. Thisvenables the pump 52 to operate all the time. It also helps to keep thespray solution mixed and, by maintaining circulation, makes it possibleto eliminate parts. However (when the nozzle tubes 21 have been moved totheir downwardly extending posi: tion), the lever system may be operatedto close the valve 58 and openthe valve 61, so that the pump 52 thenpumps liquid from the tank 50 into the boom 20. As pressure builds upinside the boom passage 39, the liquid forces open the valve 37 and theliquid then passes into the nozzles 21 and is dispensed from the lowerend 3610f the nozzles 21.

In operation, therefore, the airplane spraying unit'is normally disposedwith the valve 58 open, the valve 61 closed, and the nozzles 21 in theirhorizontal position. When the plane 10 takes off, everything remains inthis position, but as the plane .10 gathers speed, air drives the fan 54and therefore operates the pump 52 which, at this time, merely returnsthe liquid to the tank 50. The pilot prepares to spray by unlocking thelever handle 28 from the latch 33 and moves the handle 28 forward. Thevanes 34 then assist in rotating the boom 20 tomove the nozzles 21 down.When the nozzles 21 are in the spraying position, the cable 73 is usedat the beginning of each run to open the valve 61 and close the valve 58and so send liquid under pressure into the boo-m 20. The pressure of theliquid in the boom passage 39 opens the valve 37 and sends liquid out tothe nozzles 21, where it falls ofi the lower tips 36. There is no needto provide any special venturi action or anything at the tips of thenozzles, because the sweep of the wind at the end of the nozzles seemsto draw the liquid out in the desired form. At the end of each run, thelever system is operated by the cable. 73 to close the valve 61'and openthe valve 58.

At the endof the spraying operation; the boom 20 is rotated by thehandle 28 back to place the tubes 21 in their horizontal position, priorto landing the airplane.

To those skilled. in the art to which this invention relates, manychanges in construction and widely ditiering embodiments andapplications of the invention will suggest themselves without departingfrom the spirit and scope of the invention. The disclosures and thedescription herein are purely illustrative and are not intended to beinany sense limiting.

I claim:

1. An airplane spraying unit including in combination an airplane havinga wing, a fuselage, and landing gear; a hollow boom of substantiallength rotatably supported by said airplane below said fuselage andbelow and paral lel to said wing; means for pumping spray solution intosaid boom under pressure; a series of nozzle tubes connected to saidboomand extendingtransversely thereto; and means for rotating said boomfrom a position where said nozzle tubes are generally horizontal andabove said landing gear to a position where saidnozzle tubes extenddownwardly to a level below said'landing gear and below the-turbulentairstream provided by. the wing and landing gear when said airplane. isin flight.

2. An airplane spraying unit for anairplane having a wing, a fuselage,anda landing gear comprising a laterally extending spray means ofsubstantial length movably supported bysaid airplane abovesaid landinggear, below said fuselage, andbelow and. generally parallel to saidwing, said spray means having a series of. orifice means; a stationarystorage tank for spray solution; means for pumping spray solution fromsaid tank to said orifice means under pressure; andpivotally mountedmeans for rotating the position of said orifice means from a positionabove said landing gear to a position below said landingv gear and forholding themineach of said positions.

3. An airplane spraying unit including in combination anairplane havinga winganda fuselage; a hollow boom rotatably supportedby said airplanebelow said fuselage and below and parallelto said wings; means forpumping spray solutioninto said boom under pressure; a series of nozzletubes. of substantial length connected to said' boom and extendingtransversely thereto; and means for rotating said boom from a positionwhere said nozzle tubes-extend rearwardly and generally horizontal to aposition where said nozzle t uhes extend downwardly, said means forrotating said boom includinga mechanical lever system and vane meanssecured to said boom opposite to said nozzle tubes so as to besubstantially hori zontal'whenth'ey are horizontal and vertical whenthey are vertical, said vane means assisting-said mechanical leversystem in lowering said nozzle tubesby utilizing the air forcethereagainst and also assisting in maintaining said nozzle tubes intheir downward position.

'4. An airplanespraying unit including in combination an airplane;having'a wing, a fuselage, and alanding gear; a hollow boom rotatablysupported by. said airplane above said landing gear, below saidfuselage, and below and parallel to said wing; a storage tank for spraysolution; means for pumping spray solution from said tank underpressure; a series, of pressure-operated check valves on said boom; aseries of nozzle tubes of substantial length, each connected to a saidcheck valve and extending transversely to said boom; and means forrotating said boom from a position where said nozzle tubes extendgenerally rearwardly and above said landing gear to a position where theoutboard ends of said nozzle tubes extend downwardly below said landinggear, said means for rotating said beam including a mechanical leversystem and vane means secured to said boom opposite to said nozzle tubesso as to be substantially horizontal when they are horizontal andvertical when they are vertical, said vane means assisting saidmechanical lever system in lowering said nozzle tubes by utilizing theair force thereagatinst and also assisting in maintaining said nozzletubes in their downward position.

References Cited in the file of this patent UNITED STATES PATENTSDoucette Jan. 20,

Pierson Apr. 18, 1950 Sands Ian. 5,

Sellers Nov. 27,

FOREIGN PATENTS Great Britain Oct 15,

Denmark Feb. 7,

OTHER REFERENCES Aviation Week Magazine, Jan. 7, 1952, vol. 56, N0. 1,

15 page 15.

1. AN AIRPLANE SPRAYING UNIT INCLUDING IN COMBINATION AN AIRPLANE HAVINGA WING, A FUSELAGE, AND LANDING GEAR; A HOLLOW BOOM OF SUBSTANTIALLENGTH ROTATABLY SUPPORTED BY SAID AIRPLANE BELOW SAID FUSELAGE ANDBELOW AND PARALLEL TO SAID WING; MEANS FOR PUMPING SPRAY SOLUTION INTOSAID BOOM UNDER PRESSURE; A SERIES OF NOZZLE TUBES CONNECTED TO SAIDBOOM AND EXTENDING TRANSVERSELY THERETO; AND MEANS FOR ROTATING SAIDBOOM FROM A POSITION WHERE SAID NOZZLE TUBES ARE GENERALLY HORIZONTALAND ABOVE SAID LANDING GEAR TO A POSITION WHERE SAID NOZZLE TUBES EXTENDDOWNWARDLY TO A LEVEL BELOW SAID LANDING GEAR AND BELOW THE TURBULENTAIRSTREAM PROVIDED BY THE WING AND LANDING GEAR WHEN SAID AIRPLANE IS INFLIGHT.